U.S. patent number 8,360,591 [Application Number 12/478,023] was granted by the patent office on 2013-01-29 for backlight unit for liquid crystal display device.
This patent grant is currently assigned to Samsung Electronics Co., Ltd.. The grantee listed for this patent is Jong-hoon Jung. Invention is credited to Jong-hoon Jung.
United States Patent |
8,360,591 |
Jung |
January 29, 2013 |
Backlight unit for liquid crystal display device
Abstract
Provided is a backlight unit for a liquid crystal display
device. The backlight unit includes: a chassis; a printed circuit
board connected to a side of the chassis, the printed circuit board
including a plurality of light emitting diodes, and a pair of
conductive pads through which power is supplied to the light
emitting diodes, wherein the pair of conductive pads are disposed
on an end of the printed circuit board; and a power socket into
which the pair of the conductive pads are inserted.
Inventors: |
Jung; Jong-hoon (Suwon-si,
KR) |
Applicant: |
Name |
City |
State |
Country |
Type |
Jung; Jong-hoon |
Suwon-si |
N/A |
KR |
|
|
Assignee: |
Samsung Electronics Co., Ltd.
(Suwon-si, KR)
|
Family
ID: |
41414584 |
Appl.
No.: |
12/478,023 |
Filed: |
June 4, 2009 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20090310339 A1 |
Dec 17, 2009 |
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Foreign Application Priority Data
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Jun 17, 2008 [KR] |
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10-2008-0057025 |
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Current U.S.
Class: |
362/97.1;
439/325; 439/329; 439/328; 362/249.02; 362/612 |
Current CPC
Class: |
G02F
1/133603 (20130101); G02F 1/133608 (20130101); G02F
1/133612 (20210101) |
Current International
Class: |
G09F
13/04 (20060101); G09F 13/08 (20060101) |
Field of
Search: |
;362/97.1-97.4,612,555,561,219,249.02,249.04,249.06
;439/325,328,329 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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2004-55160 |
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Feb 2004 |
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JP |
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2004-199896 |
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Jul 2004 |
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JP |
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10-2007-0025825 |
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Mar 2007 |
|
KR |
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10-2007-0071543 |
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Jul 2007 |
|
KR |
|
10-2008-0032757 |
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Apr 2008 |
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KR |
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WO 2005086865 |
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Sep 2005 |
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WO |
|
Other References
Communication dated Apr. 4, 2012 issued by the Mexican Patent
Office in Corresponding Mexican Application No. MX/a/2010/013573.
cited by applicant .
Communication dated Oct. 3, 2011 issued by the Mexican Patent
Office in counterpart Mexican Patent Application No.
MX/a/2010/013573. cited by applicant .
Chinese Office Action dated Feb. 28, 2012 issued in Chinese
Application No. 200980121480.4. cited by applicant .
Office Action, dated Oct. 26, 2012, issued by the Mexican Patent
Office in counterpart Mexican Application No. MX/a/2010/013573.
cited by applicant .
Office Action, dated Nov. 19, 2012, issued by the State
Intellectual Property Office of the P.R.C. in counterpart Chinese
Application No. 200980121480.4. cited by applicant.
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Primary Examiner: Allen; Danielle
Attorney, Agent or Firm: Sughrue Mion, PLLC
Claims
What is claimed is:
1. A backlight unit for a liquid crystal display (LCD) device, the
backlight unit comprising: a chassis; a printed circuit board
connected to a side of the chassis, the printed circuit board
comprising a plurality of light emitting diodes, and a pair of
conductive pads through which power is supplied to the light
emitting diodes, wherein the pair of conductive pads are disposed
on an end of the printed circuit board; and a power socket which is
fixed to at least one side of the chassis to which the printed
circuit board is connected and into which the pair of the
conductive pads are inserted.
2. The backlight unit of claim 1, wherein the power socket
comprises: a socket housing; and a pair of power supply terminals
which are formed in the socket housing and engage the pair of the
conductive pads.
3. The backlight unit of claim 2, wherein the pair of the
conductive pads are inserted into the socket housing to be
electrically connected to the pair of power supply terminals.
4. The backlight unit of claim 2, wherein the pair of power supply
terminals comprises a conductive elastic material.
5. The backlight unit of claim 2, wherein the socket housing
comprises a pair of grooves into which the pair of the conductive
pads are inserted.
6. The backlight unit of claim 2, wherein the socket housing
comprises a single groove into which the pair of the conductive
pads are inserted.
7. The backlight unit of claim 2, wherein the chassis includes a
through hole through which power supply lines for supplying power
to the pair of power supply terminals of the power socket pass.
8. The backlight unit of claim 1, wherein the pair of the
conductive pads are formed by exposing a conductive material which
is formed on the printed circuit board.
9. The backlight unit of claim 1, wherein at least one end of the
chassis is bent at a right angle to form a bent portion, and the
printed circuit board is connected to an inner surface of the bent
portion of the chassis.
10. The backlight unit of claim 1, wherein the printed circuit
board has a strip shape, and the light emitting diodes are aligned
on the printed circuit board in a line.
11. The backlight unit of claim 1, wherein the end of the printed
circuit board is branched into two portions and the pair of
conductive pads are formed on the branched portions.
12. The backlight unit of claim 1, wherein a width of the end of
the printed circuit board is narrower than other portions of the
printed circuit board.
13. An edge light emitting type light emitting diode (LED)
backlight unit for a liquid crystal display (LCD) device, the
backlight unit comprising: a chassis; a printed circuit board
connected to a side of the chassis, the printed circuit board
comprising a plurality of light emitting diodes, and a pair of
conductive pads formed on an end of the printed circuit board; a
power socket which is fixed to at least one side of the chassis to
which the printed circuit board is connected and into which the
pair of the conductive pads are inserted.
14. The backlight unit of claim 13, wherein the power socket
comprises: a socket housing; and a pair of power supply terminals
which are formed in the socket housing and engage the pair of the
conductive pads.
15. The backlight unit of claim 14, wherein the socket housing
comprises a pair of grooves into which the pair of the conductive
pads are inserted.
16. The backlight unit of claim 14, wherein the socket housing
comprises a single groove into which the pair of the conductive
pads are inserted.
17. The backlight unit of claim 13, wherein the pair of the
conductive pads are formed by exposing a conductive material which
is formed on the printed circuit board.
18. The backlight unit of claim 13, wherein the end of the printed
circuit board is branched into two portions and the pair of
conductive pads are formed on the branched portions.
19. The backlight unit of claim 13, wherein a width of the end of
the printed circuit board is narrower than other portions of the
printed circuit board.
Description
CROSS-REFERENCE TO RELATED PATENT APPLICATION
This application claims the priority from Korean Patent Application
No. 10-2008-0057025, filed on Jun. 17, 2008, in the Korean
Intellectual Property Office, the disclosure of which is
incorporated herein in its entirety by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a backlight unit for a liquid
crystal display device, and more particularly, to a backlight unit
for a liquid crystal display device using a light emitting diode
(LED) as a light source.
2. Description of the Related Art
A liquid crystal display (LCD) device is a type of light receiving
display device that form images by receiving external light instead
of using self-emitting light, unlike a plasma display panel (PDP)
and a field emission display (FED). Thus, an LCD has a backlight
unit for emitting light to a liquid crystal layer at a rear surface
thereof.
A related art backlight unit for an LCD device uses a cold cathode
fluorescent lamp (CCFL) as a light source. However, when a CCFL is
used as a light source, brightness may be decreased and it is
difficult to secure uniform brightness as the screen size of the
LCD device increases. Thus, in order to overcome these problems, a
backlight unit using light emitting diodes (LEDs) as a light source
has been developed recently.
FIG. 1 is an exploded perspective view of a related art backlight
unit for a LCD device, which uses LEDs as a light source. In
particular, the backlight unit illustrated in FIG. 1 is an edge
light emitting type LED backlight unit.
Referring to FIG. 1, one end of a chassis 100 is bent at a right
angle to form a bent portion 100a. A printed circuit board (PCB)
120, on which a plurality of LEDs 121 are aligned, is connected to
an inner surface of the bent portion 100a. A connector 140 for
supplying power is formed at one end of the PCB 120. The connector
140 is electrically connected to a housing 150 which includes power
supply terminals. The housing 150 is connected to power supply
lines 151a and 151b for supplying power, and the chassis 100 has a
through hole 160 through which the power supply lines 151a and 151b
pass. According to FIG. 1, the PCB 120 is connected to one side of
the bent portion 100a using screws 130 that engage first screw
holes 105 formed in the bent portion 100a and second screw holes
125 formed in the PCB 120. A light guide plate which guides light
emitted from the LEDs 121 to a liquid crystal layer (not shown) of
the LCD device is aligned at an inner portion of the chassis
100.
In order to manufacture a backlight unit having the structure
described above, the housing 150 is connected to the connector 140
of the PCB 120, and the PCB 120 is connected to one side of the
bent portion 100a. However, the related art backlight unit needs to
include elements such as the connector 140 and the housing 150, and
the time required to manufacture the unit may be increased since
the PCB 120 and the chassis 100 are assembled after the housing 150
and the connector 140 are assembled.
SUMMARY OF THE INVENTION
The present invention provides a backlight unit for an LCD using an
LED as a light source, whereby the backlight unit can be
manufactured inexpensively using a relatively simple process.
According to an aspect of the present invention, there is provided
a backlight unit for an LCD device, the backlight unit comprising:
a chassis; a printed circuit board connected to at least one side
of the chassis, comprising a plurality of light emitting diodes
aligned in a predetermined shape, and comprising a pair of
conductive pads for supplying power to the light emitting diodes,
wherein the pair of conductive pads are disposed at least one end
of the printed circuit board, respectively; and a power socket into
which the pair of the conductive pads are inserted,
respectively.
The power socket may be fixed to at least one side of the chassis.
The power socket may comprise: a socket housing; and a pair of
power supply terminals corresponding to the pair of the conductive
pads and formed in the socket housing. The pair of the conductive
pads may be inserted into the socket housing to be electrically
connected to the pair of power supply terminals.
The pair of power supply terminals may comprise a conductive
elastic material.
The socket housing may comprise a pair of grooves into which the
pair of the conductive pads are inserted. The socket housing may
comprise a single groove into which the pair of the conductive pads
are inserted.
The chassis may have a through hole through which power supply
lines for supplying power to the pair of power supply terminals of
the power socket pass.
The pair of the conductive pads may be formed by exposing a
conductive material which is formed on the printed circuit
board.
At least one end of the chassis may be bent at a right angle to
form a bent portion, and the printed circuit board is connected to
an inner surface of the bent portion of the chassis. The printed
circuit board may have a strip shape, and the light emitting diodes
are aligned on the printed circuit board in a line.
According to another aspect of the present invention, there is
provided an edge light emitting type LED backlight unit for an LCD
device comprising a plurality of LEDs on at least one side of a
chassis, the backlight unit comprising: a printed circuit board
connected to at least one side of the chassis, comprising a
plurality of light emitting diodes aligned in a predetermined
shape, and comprising a pair of conductive pads at least one end of
the printed circuit board; and a power socket, fixed to at least
one side of the chassis, into which the pair of the conductive pads
are inserted, respectively.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other aspects of the present invention will become
more apparent by describing in detail exemplary embodiments thereof
with reference to the attached drawings in which:
FIG. 1 is an exploded perspective view of a related art backlight
unit for an LCD;
FIG. 2 is an exploded perspective view of a backlight unit for an
LCD, according to an exemplary embodiment of the present
invention;
FIG. 3 is a perspective view of a power socket that may be used in
the backlight unit illustrated in FIG. 2, according to an exemplary
embodiment of the present invention;
FIGS. 4A and 4B are perspective views of conductive pads of PCBs
which can be inserted into the power socket illustrated in FIG. 3,
according to exemplary embodiments of the present invention.
FIG. 5 is a perspective view of a power socket that may be used in
the backlight unit illustrated in FIG. 2, according to another
exemplary embodiment of the present invention; and
FIGS. 6A and 6B are perspective views of conductive pads of PCBs
which can be inserted into the power socket illustrated in FIG. 5,
according to exemplary embodiments of the present invention.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS OF THE INVENTION
Hereinafter, exemplary embodiments of the present invention will
now be described more fully with reference to the accompanying
drawings. In the drawings, like reference numerals in the drawings
denote like elements, and the thickness and size of elements are
exaggerated for clarity.
The present invention provides an edge light emitting type LED
backlight unit using a plurality of LEDs as a light source in which
the LEDs are aligned on one side or on both sides of a chassis.
FIG. 2 is an exploded perspective view of a backlight unit for an
LCD according to an exemplary embodiment of the present invention.
Referring to FIG. 2, the backlight unit for an LCD includes a
chassis 200 including a bent portion 200a bent at a right angle
relative to the chassis 200, a PCB 220 connected to a first side of
the bent portion 200a, and a power socket 250 fixed to the first
side of the bent portion 200a. Screws 230, first screw holes 205
formed in the bent portion 200a, and second screw holes 225 formed
in the PCB 220, are used to connect the PCB 220 to the bent portion
200a.
A plurality of LEDs 221 are aligned on the PCB 220. In this regard,
the PCB 220 may have a strip shape, and the LEDs 221 may be aligned
on the PCB 220 in a predetermined configuration, for example, in a
line. However, the LEDs 221 may be aligned in various shapes
without limitation. In addition, even though the LEDs 221 may be
aligned with one another on the PCB 220 in a line as illustrated
FIG. 2, the LEDs 221 may be aligned in two or more lines.
A pair of conductive pads 220a and 220b are formed at one end of
the PCB 220 to supply power to the LEDs 221. The conductive pads
220a and 220b correspond to a pair of power supply terminals 252a
and 252b formed in a power socket 250 which will be described
later. In addition, the power socket 250 is fixed to the first side
of the bent portion 200a to which the PCB 220 is connected. The
power socket 250 is electrically connected to the conductive pads
220a and 220b formed at one end of the PCB 220 to supply power to
the LEDs 221. The power socket 250 is connected to power supply
lines 251a and 251b which supply power, and a through hole 260 may
be formed in the bottom of the chassis 200 through which the power
supply lines 251a and 251b pass.
FIG. 3 is a perspective view of the power socket 250 that may be
used in the backlight unit illustrated in FIG. 2, according to an
exemplary embodiment of the present invention. FIGS. 4A and 4B are
perspective views of exemplary embodiments of the conductive pads
220a and 220b, and conductive pads 220'a and 220'b of the PCB 220
and a PCB 220', respectively, which can be inserted into the power
socket 250 illustrated in FIG. 3.
Referring to FIG. 3, the power socket 250 includes a socket housing
255 fixed to the first side of the bent portion 200a, a pair of
grooves 256a and 256b formed in the socket housing 255, and a pair
of power supply terminals 252a and 252b formed in the grooves 256a
and 256b, respectively. In this regard, the pair of the grooves
256a and 256b are separated from each other by the socket housing
255. One end of the PCB 220 illustrated in FIG. 4A or the PCB 220'
illustrated in FIG. 4B is inserted into the pair of the grooves
256a and 256b.
Referring to FIG. 4A, one end of the PCB 220 is branched off into
two portions, and the pair of conductive pads 220a and 220b are
formed on the branched portions. In this regard, the pair of the
conductive pads 220a and 220b are formed so as to correspond to the
pair of power supply terminals 252a and 252b formed in the power
socket 250. Accordingly, the pair of the conductive pads 220a and
220b are inserted into the grooves 256a and 256b of the power
socket 250 to be electrically connected to the pair of the power
supply terminals 252a and 252b. In this regard, the power supply
terminals 252a and 252b in the power socket 250 may be formed of a
conductive elastic material such as a metal spring for easy contact
with the conductive pads 220a and 220b. In addition, the conductive
pads 220a and 220b may be formed by exposing a conductive material
which is formed on the PCB 220. That is, if a conductive material
which is covered with an insulating layer is formed on the PCB 220,
the conductive pads 220a and 220b may be formed by removing the
insulating layer to expose the conductive material.
FIG. 4B is a modified example of the terminal of the PCB shown in
FIG. 4A. Referring to FIG. 4B, the PCB 220' is similar to the PCB
220 of FIG. 4A, except that the width of the PCB 220' is greater
than that of the PCB 220. Thus, more LEDs 221 (FIG. 2) may be
aligned on the PCB 220' having a greater width than that of the PCB
220. In FIG. 4B, the PCB 220' includes a pair of conductive pads
220'a and 220'b corresponding to the pair of power supply terminals
252a and 252b formed in the power socket 250.
As described above, the power socket 250, into which the conductive
pads 220a and 220b formed at one end of the PCB 220 or the
conductive pads 220'a and 220'b formed at one end of the PCB 220'
are inserted, is fixed to the first side of the bent portion 200a
of the chassis 200 in the backlight unit for a LCD. Accordingly,
there is no need for elements such as a connector formed on the PCB
and a housing connected to the connector which are required for a
conventional backlight unit as illustrated in FIG. 1. Thus,
manufacturing costs may be reduced. In addition, in order to
fabricate a backlight unit for LCD according to the present
invention, one end of the PCB having a pair of conductive pads may
be inserted into the power socket which is fixed to the chassis.
Thus, manufacturing processes may be simplified.
FIG. 5 is a perspective view of a power socket 350 that may be used
in the backlight unit illustrated in FIG. 2, according to another
exemplary embodiment of the present invention. FIGS. 6A and 6B are
perspective views of conductive pads 320a and 320b, and conductive
pads 320'a and 320'b of PCBs 320 and 320', respectively, which can
be inserted into the power socket 350 illustrated in FIG. 5,
according to embodiments of the present invention.
Referring to FIG. 5, the power socket 350 includes a socket housing
355 fixed to the first side of the bent portion 200a, a single
groove 356 formed in the socket housing 355, and a pair of power
supply terminals 352a and 352b formed in the groove 356. One end of
either the PCB 320 or the PCB 320' illustrated in FIG. 6A or 6B is
inserted into the groove 356.
Referring to FIG. 6A, the pair of conductive pads 320a and 320b are
formed on one end of the PCB 320. In this regard, the pair of the
conductive pads 320a and 320b are formed so as to correspond to the
pair of power supply terminals 352a and 352b formed in the power
socket 350. Accordingly, the pair of conductive pads 320a and 320b
are inserted into the groove 356 of the power socket 350 to be
electrically connected to the pair of the power supply terminals
352a and 352b. In this regard, the power supply terminals 352a and
352b of the power socket 350 may be formed of a conductive elastic
material such as a metal spring for easy contact with the
conductive pads 320a and 320b. In addition, the conductive pads
320a and 320b may be formed by exposing a conductive material which
is formed on the PCB 320.
FIG. 6B is a modified exemplary embodiment of the terminal of the
PCB shown in FIG. 6A. Referring to FIG. 6B, the PCB 320' is similar
to the PCB 320 of FIG. 6A, except that the width of the PCB 320' is
greater than that of the PCB 320. Thus, more LEDs 221 can be
aligned on the PCB 320' having a greater width than that of the PCB
320. In FIG. 6B, the PCB 320' includes a pair of conductive pads
320'a and 320'b corresponding to the pair of power supply terminals
352a and 352b formed in the power socket 350.
The power sockets 250 and 350 and one end of the PCBs 220, 220',
320 and 320' illustrated in FIGS. 3 to 6B are described for
illustrative purposes only. The exemplary embodiments described
above may be modified in various forms by those skilled in the art,
and the scope of the present invention is not limited to these
embodiments.
Furthermore, even though it has been described that the PCB
including LEDs is formed on only one side of the chassis, the PCB
can also be formed on the other side of the chassis. In addition,
even though it has been described that a pair of conductive pads
are formed on only one end of the PCB, the conductive pads can also
be formed on the both ends of the PCB. In this regard, two power
sockets which correspond to the two pairs of the conductive pads
formed on both ends of the PCB can be fixed to one side of the
chassis.
As described above, according to the present invention, a backlight
unit for a LCD can be manufactured inexpensively and using a
relatively simple process.
While the present invention has been particularly shown and
described with reference to exemplary embodiments thereof, it will
be understood by those of ordinary skill in the art that various
changes in form and details may be made therein without departing
from the spirit and scope of the present invention as defined by
the following claims.
* * * * *